Searchlight



July 3, 1928.

C. B. MILLS SEARCHLIGHT Filed Aug. 26. 1922 4 .Sheets-Sheel 5 ,2 r /fln 'July 3, 192s.

C. B. MILLS smcnucm 'Filed Aug. 26. 1922 4 sheets-sheet 2 -y .Ef

July 3, 192,8.

C. B. MILLS sEARcHLIGH'r Filed Aug. 26; 1922 4 Sheets-Sheet `3 ammo@ mf. gf-4155 mw /Wl//i N @127W July 3, 1928. 1,615,720

C. B. MILLS SEARCHLIGHT Filed Aug. 261922 f 4 Sheets-Sheet 4 nvantoz Hrm/M/s. @@g; wmwj l.

, to bemounted onfcraft such as destroyers.4 ,40

Patented July 3, 1928-.k

. UNITED STATES 1,615,120 PATENT OFFICE.

CHESTER B. HILLS, 0F BROOKLYN, NEW YORK, ASSIGN'O'B TO SPERBY GYBOSOOPI OOI- OF BROOKLYN, NEW YORK, A CORPORATION 0F NEW YOBK..

smcnmem".

' appncama mea august 2e, 1922. smal m. 584,399.

This invention relates `to high-intensity searchlights designed particularly for use upon small naval craft such as destroyers and submersible craft. It has been found impracticable to utilize the standard naval type of searchlight on submersible craft, since this involved the necessity of roviding a water-tight hatch into whic said searchlight could be lowered for protection. 'It is one object of this invention to provide a searchlight having a water-tight drum,

thus obviating the 'necessity for a water-l form of high-intensity searchli ht.

tight hatch. I

It is a further object of this invention to provide a searchlight drum capable ofwith- "standing the water pressures met with in ordinary diving, and maneuvering.

' A- further object is the provision of means for automatically 'preventing the collapse of the said drum under Apressures greater than those met with lin ordinary diving and maneuvering.

A further object is the provision of Aa searchlight mounting'whereby the searchlight may be quickly operated to effective or ineffective position;v

A further object'of this invention is the F provision of a water-tight searchlight drum having communication with the atmosphere only through a ventilation passage, and having means for rapidly closing or opening said passage.

A. `further object-is the provision of a lamp I which is inexpensive, of simple construction, light in weight,.and of high eiciency, said searchlight comprising cast metal parts. This construction rmits a standard searchlight, such as thel perry high-intensity lamp,

Their use upon such'crat was hitherto prei" vented because'their great weight on the necearily elevated towers materially ,lowered the Vmetacentric height of the craft and induced lsevere rollingl and instability even under ordinary'gsea conditions. The cast metal parts permit a light material, such as an aluminum alloy, to* be u's'ed, and also obviate the of a great many. connecting members, such as bolts, screws and the like,

which ordinarily materially vincrease the v weight ofthe lamp.

` Other objects and advantages will be in part obvious andin part specificallypointed out inthe specification. i

the accompanying therefrom at the rear.

.20 divided Fig. 1 is side view, partly sectioned vertlcally, of 'a high-intenslty searchlight mounted on the deck of a submersible vessel. Flg. 2 is a front view of the Ventilating inlet and outlet passages, showing a' portion of the cover-lock construction.

Fig. 3 isa vertical section through a portion of the Ventilating system.

Fig. 4 is a vertical section showing a moditied mounting of the cover for the ventilatlngvmlet Zand 'outlet passa 1g. 5 is a front elevation of a second Fig. 6 is a side elevation o the searchligllit shown in Fig. 5. f f

i 7 is a verticalsection throu h the drum of the searchlight shown in igs.'5 and 6. Y

Fig. 8 is a vertical section showing a portion of the ventilating system.

Fig. 9 is an inner view of the cover showin ith'e v entilati v i ig. 10 is a vertical section through the cover. Y,

Fig. 11 is a section!E taken through one of the Ventilating passages in the cover.

ig. 12 is a vertical section through the r'portion ofthe searchlight drum.

ig. 13 is al1-enlarged view, artly sectioned vertically, of the end o? the compressed air tank having an automatic valve attached thereto.

Fig. 14 is a vertical-section through a portion of the searchli ht drum and an automatic valve ap li thereto.

vReferring to igs. 1 to 4 inclusive, there is shown a hi -intensity searchlight which 'comprises a rum having a cast-metal, jointleasmain-body or barre 10, a lens or dgla window 11 at the front curved outwar ,y to withstand greater pressure, and a mirror 12 (see Fig. 3) protected b a cover 13 s eed aid cover an rel may be provided with cooperating flanges 14 and 15, respectlvely, whereby sal cover may be attached to said barrel, as by thumb-screws 16. A. washer is inte between the anges to render the 'oint watertight. Both the transparent win ow andthe mirror are set ingaskets, such as 17 1n Flg. 3 to form water-tight 'oints. ast preferably integr'al with the body 10 1s a housing f 22 and 23, the former communicat- 1 .e leading from the fan or barlas

by a partition 21 to form two other air-current-producing device 25 in said housing, and the latter communicating with the space between mirror 12 and cover 13. By this arrangement a current of air is blown out from the interior of the lamp to the outside through passage 22, said air being replaced by a cool current entering through passage 23 and flowing between the mirror 12 and the cover 13 through a plurality of distributing ports 30 in the lower portion of the cover V(see Fig. 8) and thence into the body of the lamp.

It will be apparent from the foregoing description that the drum has but one source of communication with the exterior, i. e., through the opening in housing 20, but is otherwise absolutely water-tight. When the drum is to be submerged, the opening in housing 2O leading to the outlet and inlet passages 22 and 23 may be closed by a cover or cap applied to said opening in any suitable manner to form a water-tight closure. As shown, housing 20 is provided adjacent said opening with a plurality of spaced segmental langes 32, said flanges being in the form of cams or screw threads. The cap is provided with grooved projections 36 also in the form of cams or screw threads adapted to be inserted in the spaces between flanges 32 and then, by approximately a quarter turn, engage over the flanges. The construc.

tion is similar to that used in breech-blocks. For easy handling, the cap may be provided with handles 37, and to prevent its detachment from the drum a chain 38 may be fixed at one end to the cap and at the other end to the drum or housing. The usual washer 29 may be interposed between the cap 'and the open end of the housing 20.

A modified mounting for the cap is illustrated in Fig. 4. In this construction the cap is slidable toward or away from the opening upon a rod 40 threaded at one end into the partition 2-1 and extending through a central hub 41 in the cap. lMeans, such as a spring detent 42, may be provided to hold the cap in outward position when thelight, and hence the Ventilating system, is in operation.

. The application of the water-tight drum, as hereinafter described, to a submarine vessel, is illustrated in Fig. 1, wherein the main deck of said vessel is indicated at and the inner, water-tight deck is indicated at 51. The drum may be pivoted in trunnions 52 fixed upona post or support 53 extending through an opening in the maindeck 50 and pivoted in a bracket 54 fixed to the deck 51. The opening 55 is large enough to permit the post and lamp to be swung from elevated or effective position (as shown by the full lines) to lowered or ineil'ective osition ('as shown b the-dotted lines) be ow the main deck. e raising vand lowering operations may be facilitated by a dashpot 56, pivoted at one end upon a bracket 57 fixed to the deck 51 and in which operates a piston 58 connected by a link 59 to the lower end of post 53. W'ithin the dash-pot is ositioncd a spring 60 normally tending to ibrce piston 58 to the outer end of the dash-pot and raise the lamp.

lVithout providing any water-tight coni- Eartments, it is apparent that the lamp may e safely and rapidly stored below the main deck. The searchlight drum being watertight, filling of the space between decks 50 and 51 with water will not affect the lamp. The drum is constructed of non-corrosive, preferably light material, such as an aluminum alloy. The electric connections may extend through post 53 and one of the trunnions 52 to the lamp. The drum may be raised or lowered about its pivots by means of a hand-wheel 62, and may be held in position by a set-screw 63 operating in a slot 64 in wheel 62.

The drum is constructed to withstand any desired external water pressure Without leaking, e. g., a pressure equivalent to a hydraulic head of 75 ft., beyond which the searchlight will seldom be carried in ordinar diving or maneuvering of a submersib e craft. Means may be provided however, which permit submersion beyond the calculated safe depth without injury to the lamp. For this purpose, there may be provided 1n the stowing quarters between decks 50 and 51 a tank 65 carrying air under pressure and connected to the interior of the searchlight drum, as by a metallic hose 66. The tank may be provided with some well-known form of valve, such as a diaphra valve, adapted to discharge automaticalyl, when the predetermined safe depth of submergence ft., say,) is exceeded, a sufiicient uantity of air into the drum so that the diference of pressure between the outside and inside of the drum does not exceed the predetermined safe pressure. This valve may take the form shown in Fig. 13 and comprises a chamber 101 fixed in any suitable manner to the compressed air tank and having a passage 102 communicating with the interior of the tank. Said passage is normally closed by a valve 103 at one end of a valve stem 104, the other end of which is fixed to a diaphragm 105, which r divides chamber 101 into two compartments'106 and 107. A spring 108 pressing at one end against a xed shoulder/109 and connected at its other end to the valve stem normally presses the diaphragm outwardly and closes the valve against its seat 110. The compartment 107 is in communication with the outside by a. plurality of openings 111, while the compartment 106 is in communication with the interior of the searchlight drum by cable 66. It will be apparent that the tension of spring 108pmay such that when the inside thereof, the pressure of the sea water upon the diaphragm will unseat valve 103 and permit compressed air to enter the drum and reduce the pressure differential. The tension of spring 108 may be varied by means of nut 112 threaded upon the end of stem 104 and abutting against valve 103.

The drum may be provided with a similar valve so that when the vessel rises to the surface the excess pressure therein may be automatically relieved. For this purpose, there may be provided the valve illustrated in Fig. 14. Said valve operates in a housing formed bya plate 120' having an innerthreaded flange 121 co-operating with a threaded opening cut in the drum 64, and having an outer threaded flange 122 on which is threadedl a casing 123. Plate 120 is provided with a substantially central boss 125 provided witha plurality of bores 124. Through 'the central bore operatesa valve stem 126 having a valve 127 at its upper end cooperating-with the bores. A spring 128 abuts at one end against the inner surface of hub 125 and at the other end against a flanged disc 130, threaded on the end. of the valve stem and adjusted in position by locknuts 131 to vary the tension of spring 128. The spring thus normally holds the valve in closed position. The casing 123 is provided with a-plurality of openings 135 to permit communication between the interior and the exterior thereof. It will be obvious that when the outside pressure falls sulliciently, the pressure within drum 64 operating on the valve through bores 124 will overcome the tension of the spring and unseat the valve, thus allowing a reduction of the internal pressure. It will be understood that the Valve structure hereinbefore described is merely 'illustrative of the principle involved, but that other well-known types of valves may be substituted therefor.

,In Figs. 5-12y there is illustrated a second form of searchlight suitable for use upon destroyers and other light, swift craft. One of the main considerations in searchlights of this type is that of 'Weight which must be reduced to a minimum in order not to lower the metacentric height of the craft and render it unstable. At the same time it is desirable to obtain as power-ful a light as possible, which necessitates utilizing searchlights in excess of the 24 type and of correspondingly great weight. To permit the use r of large lamps upon light craft this inven- `tion provides a construction whereby the weight of said lamps is materially reduced. For this purpose the lamp comprises a drum pivotally mounted in trunnions 71 of a member 72 rotatably mounted on a base 73. The drum comprises a main casing or barrel coinprislng the drum, as well as the trunnion member 72 and the base 73 are in the form of castings made of a light metal such as an aluminum alloy. The barrel 75is formed integral with the container 78 for the usual control mechanism including a switch which may be operated from the outside by aD handle 79. The barrel is preferably formed complete for the reception of the front window at the front and with means for attaching the mirror cover at the rear. At the front an inwardly' projecting annular flange 75 is shownv as cast integrally with the barrel forming a face for the reception of the front Window as hereinafter describeda At the back the barrel is formed with an outwardly projecting annular flange `17 5 and with an integrally cast ear 176 for the re- Iception and hinging of the back 76 of the mirror. The casing 77 mayl be bolted to the top of barrel 75, and the cover 76 lmay be pivoted to the rear of said barrel and locked by latches 80. Various openings-may be provided in the main casing or barrel to allow'access to various` parts of the lamp mechanism, 'and are .normally closed by covers 81, 82, 83, 84 which are held in position by any suitable fastening means. The barrel is lprovided at the front with a windowv 85 (see Fig. 12) set in a gasket 86, and with a signaling shutter 87 operated by a handle 88 fromoutside the barrel, as is more fully disclosed in the application of Theodore -Hall, Ser.' No. 211,288, filed J an. 10, 1918. At the rear of the vvbarrelthere is mounted the mirror 89 set in a gasket 86.

The cover 76 is spaced from mirror 89 and is provided with a cut-out portionl near its top forming a passage 90 from'the outside. The entrance to said passage is protected by an overhanging portion or guard 92 integral with the cover. Air enters pas sage 90, passes down between the cover and the mirror, through a plurality of `apenings 30 (see Figs. 8 and v9)upwardly along the front of the mirror to replace the air forced out of the lamp. by the yVentilating blower 93 operated bymotor 94 within the casing 7 7 The blower drives air from the interior of the lamp through passage95 tothe exterior by way of passage 96 (see Fig. 5). The casing 77 may be spaced from barrel 75 along its lower edges as at 97 to permit any collected moisture Within casing 77 to drain. A

'Ihe drum may be rotated in its bearings by aV hand-wheel 62 and fixed in position by av 'set-screw 64 operating in'slot 63, as hereinbefore described, The usual scale 98 may be provided on the base 73 cooperating with a pointer 99 on member 72, the latter being provided with the usual reading lamp 100.

In accordance with the provisions'f the patent statutes, I have herein described the principle of operation of m .invention, to-

' gether with the apparatus w ch I now oonout by other means.

Sider-nto represent the best embodiment thereof, but I desire to have it understood that the apparatus shown `is only illustrative and that the invention can be carried Also while it is designed to use the various features-and elements in the combination and relations described, some of these may be altered and mm1 body having others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having described my invention, what I claim and desire to secure by IttersPatent 1. A searchlight drum com rising a casta latere y prolect' o housing formed mtegral therewith,

body having an opening, and a cast-metal cover for closing said opening.

2. A cast aluminum alloy searchlight drum comprising a body having a laterally prolectin wit sai bod having front and rear openings, a cast a uminum alloy cover. for sealing said rear o ning, and a glass window for sealing sai` front opening.

3. A cast metal searchlight drum com- 80 l' prising a body having a ventilation housing formed integral therewith, said body having front and rear openinis, a cover for vsealing said rear opening, sai' ventilation housing having an opening, and a detachable cover $5 for sealing said last-named opening.

In testimony lwhereof I have axed my signature. i y

, CHESTER B'. MILLS.

housing formed integral there- 25 

